Sleep and dementia have a complex relationship. Indeed, many studies The desire to find a link between poor sleep quality in aging people and the risk of developing a neurodegenerative disease has often led to conflicting results. Research conductedInstitute of Neurology Montpellier (INM) most recently published was interested in studying sleep trajectories over time by repeating various measurements (sleep questionnaires, cognitive tests, regular doctor visits, six visits in total in fourteen years) to see if changes in sleep habits occur over 65 years.
“Sleep duration was significantly increased in subjects who developed dementia during follow-up.”
To do this, the researchers conducted their work using the so-called 3C epidemiological cohort (3 Cite, Dijon, Bordeaux, Montpellier), consisting of participants aged 65 years and older, and compared two separate groups over 14 years. On the one hand, almost 700 people who did not develop dementia during follow-up, and on the other hand, 182 patients who were diagnosed with dementia during follow-up.
“We were able to model specific sleep trajectories by examining various factors such as sleep duration, time spent in bed, sleep time, wake time, daytime sleepiness and naps,” said Clemence Cavayès, an epidemiology researcher at INM. The main results of this work show that in the years prior to the diagnosis of dementia, sleep duration and time spent in bed increase more rapidly in individuals who develop dementia with earlier bedtimes. “We found that sleep duration significantly increased in subjects who developed dementia at the time of follow-up compared to those who had not developed it in the 12 years prior to diagnosis. On the other hand, there was no difference in the time of awakening, sleep or sleepiness.daytime,” the researcher clarifies.
“Sleep disorders may increase the risk of dementia”
It remains to fully understand the underlying mechanisms (oxidative stress, inflammation) and better understand the relationship between sleep and dementia such as Alzheimer’s, which researchers now consider potentially bidirectional. “This means that sleep disturbances can increase the risk of developing dementia and that the development of dementia can also lead to sleep disturbances,” Clemence Cavayès concludes. To confirm their findings, the researchers now would like to be able to continue their work with a cohort of younger subjects in their forties to see if these changes in sleep patterns occur even earlier, even before they reach the age of 40. 65. year.